Oh, so it's a bad idea to put the kiln under a roof overhang outdoors? It'll be protected from rain and dew, but will be subject to temperature variations and wind.
I've seen many kiln under shed roofs and that sort of thing, wasn't a problem. I'm talking everything from the 18" cube electric to the 7' x 7' x 8' 4-burner propane kiln. a 50 degree temperature variation means nothing to a 2500 deg kiln . Wind might be a problem if it blows out the burners.